The patent was extended for seven years. A few years into the extension, "Application for Reissue, in two divisions, filed January 8, 1874." According to the "Decisions of the Commissioner of Patents" for 1874, the reissue was rejected. There is, however, an AI (Additional Improvements) patent, for making staves.

This patent was litigated in H. H. Evarts et al. vs. David M. Ford, in front of Judge J. Blodgett of the Northern District Court of Illinois, in November 1873. "The third claim of the patent granted H. H. Evarts, October 1, 1854, for improvement in shingle-machines, which is, 'presenting the sides of the fibers of the wood to the action of the saws in the sawing of shingles or equivalent articles, for the purpose of giving them smoother surfaces than can be produced by the usual mode of sawing,' if construed literally, asserts a right to a result, and cannot be sustained. Construed as a claim for the mechanism by which the result is effected, it may be sustained. A patent for a machine in which a shingle-bolt is fastened automatically by dogged teeth upon a rotating carriage, which presents it sidewise to the saw, is not infringed by a machine in which the bolt is by hand fastened to a reciprocating carriage, and by hand shoved to the saw and withdrawn. Evarts having failed to patent his hand-machine, made while experimenting and before taking out his patent on his perfected machine, and having failed to mention or describe it in the specification of the patent he did take out, is held to have abandoned it to the public. The opinion of the Commissioner of Patents, granting an extension, is entitled to great weight on the question of novelty."

Quoting from "Reports of Cases Arising Upon Letters Patent for Invention" by Samuel Sparks Fisher: "It is an ingenious and complete machine for sawing shingles from the block. A block, T (in the engraving represented in broken lines), is placed on each table, P, P'; is seized by dogs, actuated by H, and teeth t' and carried by the saws A, as the cogged rim F revolves. The tables P, P' are so inclined in respect to saws as to give the required taper to the shingle. The lever cams H are rocked on fulcrums in the rim D, by cams n', n', so that two at a time of the dogs i shall pierce the block as it arrives near the saw, or at T, by which time the other two dogs i, which hold the block thus far, are withdrawn; thus but two dogs, together with the teeth t', carry a block around. It must be observed that, to give the proper taper, the beds P, P' slope inward and downward from the saws the angle required. As the block always bears against this bed as it meets the saws, the taper necessarily results. The block is sawed alternately from end to end, giving the thin and thick ends of shingles, alternately from each end of the block. As soon as one shingle is cleared, it drops, and the dogs i, now holding the block, are withdrawn (by cams n', n'), and the block drops a distance equal to the thickness of the shingle just formed on the bed H, and is in the exact position to meet the next saw, just before clearing which, two dogs, i, quickly clamp it, and hold it until past this saw. Thus it may be seen that a block placed on one of the tables, and the machinery being in motion, the machine will convert it into shingles without further manual assistance."